Method and apparatus for gapping and cleaning slide fastener chain

ABSTRACT

Method and apparatus for gapping and cleaning coil-filament slide fastener chain by moving an end punch having a generally trapezoidal cross-section into engagement with the coupling elements of the filamentary stringers with the stringers supported over a slotted die member. The punch transversely cuts the stringers, forces a lower leg of the coupling elements against the edges of the slot so as to longitudinally sever the same, and then seizes the severed coupling elements between the oblique side walls of the punch and the side walls of the slot to withdraw the coupling elements from the carrier tapes to form a fragment free gap end.

United States Patent Doerter [4 1 Aug. 22, 1972 [54] METHOD AND APPARATUS FOR 3,456,328 7/1969 Wasko ..29/207.5 D X GAPPING AND CLEANING SLIDE FASTENER CHAIN Primary Examiner-Thomas H. Eager 72 Inventor: Randall H. Doerter, Loris, s.c. field [73] Assignee: Textron Inc. 57] ABSTRACT Filedl 12, 1971 Method and apparatus for gapping and cleaning coil- [21] Appl' No; 114,872 filament slide fastener chain by moving an end punch having a generally trapezoidal cross-section into engagement with the coupling elements of the filamenta- US. y tringer the stringers upported over a lotted [5g] Cl. ..B23p 19/02 die member The punch transversely cuts the stringers L 1 of Search "29/408, 2075 200 207-5 forces a lower leg of the coupling elements against the edges of the slot so as to longitudinally sever the same, and then seizes the severed coupling elements [56] References and g 1 between the oblique side walls of the punch and the UNTTED STATES PATENTS side walls of the slot to withdraw the coupling elem ts f m the carrier ta es to form a fra ment free 3,128,543 4/1964 Fasciano ..29/408 i f p g 3,129,498 4/1964 Runnels ..-...29/200 D 3,368,269 2/1968 Perlman ..29/207 .5 D 14 Claims, 7 Drawing Figures PATENTEUmszz m2 3.685.130

sum rm 2 ATTOR N EYS PAIENTED M1822 Ian SHEET 2 UP 2 FIG. 4

mvsmon RANDALL H. DOERTER METHOD AND APPARATUS FOR GAPPING CLEANING SLIDE FASTENER CHAIN BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention pertains to improvements in apparatus and methods for making slide fasteners and more particularly to an improved apparatus and method for gapping and cleaning continuous coil-filament slide fastener chain.

2. Description of the Prior Art Slide fasteners of various lengths are often made by processing a continuous length of interengaged slide fastener chain which has been previously manufactured and stored in some convenient form such as a roll. One type of coupling element used in such slide fasteners if formed from a continuous length of filamentary material which has been deformed or wound into a substantially helical coil having a series of head elements interconnected by generally arcuate heel members. Such a continuous filamentary stringer may be manufactured from any suitable material, such as nylon, and is generally sewn or woven to the inner edge'of a carrier tape such that one or more individual threads pass around each arcuate heel member to secure the filamentary coil to the tape.

In order to form individual slide fasteners of a given size or length, the above described continuous slide fastener chain is fed through apparatus which severs and removes a predetermined number of interengaged coiled filament fastener elements at preselected spaced intervals along the chain. This operation is known as gapping and cleaning, and the spacing between adjacent gaps primarily determines the length of the finished slide fasteners. Of course, once the gap in the continuous chain is made and cleaned, the chain can be readily severed across the gap such that the severed units are provided with element free tape ends which can be conveniently used to attach the finished fastener to a garment.

While the prior art, as exemplified by US. Pat. Nos. 3,128,543, 3,129,498, 3,368,269 and 3,456,328 is generally cognizant of various techniques for gapping and cleaning interlocking elements from continuous slide fastener chain at spaced intervals, they have not proven entirely satisfactory since such apparatus generally does not properly cut and clean the ends of the gaps which often results in loose coil segments being left attached to the carrier tapes to cause fouling of the slider and/or irritation to the wearer after the fastener is installed in a garment. More specifically, the prior art apparatus typically employed a punch and die combination having an elongated main punch and generally rectangular end punches designed to cut out at least one fastener element at each of the gap ends and to sever a leg of those elements between the gap ends after which continued advancement of the main punch grasped each severed heel member to remove the same from its attaching threads. In actual practice, this type of apparatus has not satisfactorily cleaned the ends of the gaps and especially the top end of the gap since the spiral configuration of the filamentary stringers resulted in both legs of the fastener elements at the top end being severed leaving at least one loose coil segment still attached to the tapes by the threads. Also, the severed coil segments could not be removed by the prior art apparatus since no clearance was provided between the rectangular end punch and the cutting edges of the die to permit passage of the severed heel members down and out of the gap. As a result, the gapped chain had to be inspected and the loose coil fragments manually removed at a loss of both production time and money.

While the above problems have been recognized for a considerable period of time and a number of attempted solutions have been proposed, a simple apparatus for providing an element free gap having cleaned gap ends in a coil-type slide fastener chain has heretofore been unavailable.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to efficiently gap and clean continuous slide fastener chain employing coiled filamentary stringers.

The present invention is summarized in method and apparatus for gapping and cleaning slide fastener chain, the method being generally characterized as including the steps of positioning a group of interengaged filamentary fastener elements over an elongated slot defined by a die member; positioning an end punch member above the group of elements, the punch member being adapted to move into and out of the slot and having a generally trapezoidal cross-section with the wider parallel wall dimensionally equal to the width of the slot; moving the punch member into the slot such that the wider parallel wall cooperates with a transverse end wall of the slot to cut the filamentary stringers so as to define a gap edge; engaging the cut stringers with the punch member such that continued movement of the punch member forces a lower leg of the fastener elements against the edges of the slot to sever the fastener elements; and seizing the severed fastener elements between the oblique side walls of the end punch member and the longitudinal side walls of the slot to urge the severed fastener elements away from the gap edge while simultaneously withdrawing the same from the carrier tapes.

Another object of the invention is to thoroughly clean the gap ends of coil-filament slide fastener chain.

A further object of the present invention is to clean the top end of a gap in a slide fastener chain having a coiled filamentary stringer.

The present invention has a further object in that filamentary fastener elements at the ends of the gaps of continuous slide fastener chain are severed and removed without damaging the stitching or the carrier tapes and without leaving loose coil fragments.

Another object of this invention is to gap and thoroughly clean coiled filamentary fastener elements from slide fastener chain by a simple and inexpensive method. This invention has a further object in the construction of a simple apparatus for thoroughly cleaning or removing fastener elements from coiled filamentary slide fastener chain to provide a series of gaps free from filament fragments at both ends.

The present invention is particularly advantageous in that severed coil fragments at the gap ends of slide fastener chain are simply removed, costly on-line inspection procedures are eliminated, and slider fouling by loose coil segments or fragments is eliminated.

Other objects and advantages of the present invention will become apparent from the following description of the preferred embodiments take in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of apparatus for gapping and cleaning slide fastener chain according to the present invention;

FIG. 2 is a detail of the top end punch and die key of the apparatus of FIG. 1 with the slide fastener chain removed;

FIG. 3 is a side elevational view of the punch and die members of the apparatus of FIG. 1 with the slide fastener chain removed;

FIG. 4 is a sectional view taken on line 44 of FIG. 3; and

FIGS. 5-7 are diagrammatic views illustrating the operation of the apparatus of FIG. 1 in accordance with a method for gapping and cleaning slide fastener chain according to the present invention DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 7 of the drawings, the present invention is adapted'to operate upon a length of coiled filament type slide fastener chain 10 which includes a pair of carrier tapes 12 and 112 having secured thereto along their adjacent longitudinal edges a respective one of a pair of continuous helically wound coil filaments 14 and 114. The filaments are wound on a suitable machine into their spiral shape or configuration with the outer end of the arcuate heel members 16 and 116 deformed to provide suitable interlocking head elements 18 and 118. The continuous coil filaments 14 and 114 are then secured to the edge of the tapes by threads 20 and 120, respectively, which pass about the heel members 16 and 116 and through the tapes. Threads 20 and 120 may be applied by a separate stitching step or may take the form of braiding integrally formed with the carrier tapes. The'chain may also include bead cords 22 and 122 about which threads 20 and 120 pass for guiding a slider (not shown) in the finished product.

A preferred embodiment of apparatus for gapping and cleaning slide fastener chain of the above described type in accordance with the present invention is illustrated in FIGS. 1-4 and includes a bifurcated die 30 defining a longitudinally oriented channel or recess 32 adapted to receive the interengaged filamentary stringers 14 and 114, bead cords 22 and 122, and stitching threads 20 and 120. Recess 32 separates the flat upper surface of the die into two sections, so as to provide a pair of pressure pads 34 and 36 for the carrier tapes 12 and 112. Die 30 defines a generally rectangular, longitudinally oriented slot 38, and the floor of recess 32 is formed of a flat central surface 40 which intersects a pair of oblique surfaces 42 and 44 at a pair of ridges which form sharp cutting edges of the slot 38. A pair of removable or replaceable die keys 46 and 48 are disposed in suitable voids at respective ends of slot 38 in die 30 with the upper surfaces of the keys shaped to conform to the configuration of the slot and the channel 32.

Positioned above die 30 is a punch assembly 50 which includes a pair of support blocks 52 and 54 having flat bottom surfaces providing pressure pads for carrier tapes 12 and 112. The adjacent longitudinal bottom edges of blocks 52 and 54 are notched to form a longitudinal channel 56 similar to channel 32 for accommodating the interengaged filamentary stringers. A pair of end punches 58 and 60 and a main punch 62 are movably disposed between support blocks 52 and 54 and are attached at their upper ends to an actuating plate 64 of a suitable actuating mechanism (not shown) which may be of any conventional design for imparting reciprocal motion to the punch assembly during operation. Plate 64 is maintained in its proper position by a plurality of aligning bolts 66 which are threadedly secured to blocks 52 and 54 with the blocks and the plate biased apart by compression springs 68.

End punch 58 is generally horizontal in cross-section (FIG. 4) and has a width equal to that of slot 38 and a length'equal to at least the distance traversed by one coil of the fastener elements 14 and 114 as can be seen in FIG. 7. End punch 60 is similar to end punch 58 with the exception that the lower end thereof is laterally tapered so as to provide a generally trapezoidal crosssection (FIG. 4) with the wider parallel wall dimensionally equal to the width of the slot and the narrower wall equal to the width of main punch 62. As can be seen from the drawings, the end punches 58 and 60 abut the front and back sides of main punch 62 with the combined length of the punches equal to the length of slot 38.

As illustrated in FIG. 3, end punches 58 and 60 extend slightly below main punch 62 such that the end punches engage the slide fastener chain just before the main punch during the gapping operation. The lateral edges of end punch 60 are stone dulled and the edges of main punch 62 are preferably chamfered such that only the edges of end punch 58 and the outer transverse edge of end punch 60 act as cutting edges. All three punch members will readily be accepted in slot 38 and die 30 with the clearance between either side wall of main punch 62 and its respective adjacent side wall of slot 39 being slightly less than the thickness of the filamentary material making up the coil stringers 14 and 114 so that the filamentary material will be seized therebetween in a manner to be described below.

The above described apparatus operates in accordance with a method for gapping and cleaning slide fastener chain according to the present invention which will be explained with reference to FIGS. 1 and 5-7 of the drawings. The slide fastener chain 10 is threaded between die member 30 and punch assembly 50 with coils 22 and 122 cooperating with channel 32 in the die and channel 56 in the punch assembly to center the interengaged filamentary stringers l4 and 114 beneath punch members 58, 60 and 62 and over slot 58 in die 30. As illustrated in FIG. 7, and shown schematically in FIG. 1, the spiral or coiled nature of the interengaged filamentary stringers 14 and 114 cause the interlocked head elements 18 and 118 to assume a generally V- shaped configuration. In the production of individual slide fasteners, it has been found desirable to align the slide fastener chain such that the V-shaped interlocked elements point toward the bottom end of the fastener to facilitate operation of the slider. It can therefore be seen that with the slide fastener chain oriented as shown in FIG. 1, the gap end formed by end punch 58 will correspond to the bottom end of one individual slide fastener, and the gap end formed by end punch 60 will define the top end of an adjacent individual slide fastener.

After the slide fastener chain has been properly oriented over slot 38 as described above, actuator plate 64 is moved downwardly toward the die 30 whereupon the lower surface of support blocks 52 and 54 will engage the upper surface of the carrier tapes 12 and 112 to exert pressure thereon for securely holding the slide fastener chain on the die. Continued movement of actuator plate 64 compresses springs 68 and moves the punch members 58, 60 and 62 downwardly such that end punches 58 and 60 engage the coupling elements of the filamentary stringers at the ends of a gap to be formed. As the punch assembly is further advanced into the slot 38, end punch 58 cooperates with die key 46 to cleanly sever atleast one of the interlocked head elements 18-118 from its respective arcuate heel member of each stringer l4 and 114. At this same time, the wider parallel wall of end punch 60 slidably engages the transverse end wall of die key 48 to transversely sever the filamentary stringers so as to define a cleanly cut gap edge at the top of the adjacent slide fastener.

As the punch assembly continues to move down, the dull, oblique edges of end punch 60 and the blunt, chamfered end of main punch 62 compress the filamentary coils as illustrated in FIG. 5. As a result, the lower legs of the coupling elements are severed at the sharp cutting edges of slot 38 and the interlocked head elements 18 and 118 are driven downwardly into the slot. Continued movement of main punch 62 and end punch 60 causes the heel members of the severed coupling elements to be seized between the punches and the side walls of the slot whereupon they are rolled out from under threads 20 and 120 and withdrawn from the carrier tapes.

Referring not to FIG. 7, it can be seen that the left and right gap ends cannot be gapped in the identical manner due to the unsymmetrical nature of the wound filamentary stringers produced by the V-shaped configuration assumed by the interlocked head elements, as briefly described above. More specifically, while the intermediate coupling elements may be efficiently removed by the action of main punch member 62- cooperating with slot 38 of die 30, it is necessary to cleanly sever the filamentary material at the ends of the gap to prevent the extraction of the filamentary stringer ends by main punch 62 and resultant thread and tape damage. At the bottom end of the gap, illustrated to the left in FIG. 7, it is noted that the head elements 18 and 118 are disposed to the right of the arcuate heel members l6 and 116 associated therewith such that the head elements may be said to point into the gap due to the aforementioned stringer unsynunetry. Thus, as the rectangular end punch 58 is moved into the slot 38, the filamentary stringers will be cleanly severed, with the heel members of those interlocked head elements disposed under punch 58 cut such that the severed segments may be withdrawn from the carrier tapes in the direction of the arrows by main punch 62. In other words, a cleanly cut gap edge will be produced by punch 58 with adjacent severed filament fragments being disposed such that they may be rolled out to the right (as visualized in FIG. 7) and withdrawn from the carrier tapes by main punch 62.

At the right end of the gap, it can be seen that due'to the stringer unsymmetry the interlocked head elements 18 and 118 are displaced to the right of their associated heel members such that the main punch 62 or a rectangular end punch similar to punch 58 would not be able to completely remove all of the severed coiled fragments to provide a clean gap edge. In other words, since the stringer unsymmetry causes each coupling element to be severed and rolled out to the right, as shown in FIG. complete cutting of the heel members at the right end of the gap tends to leave loose fragments attached to the tapes, which fragments would have to be rolled out to the left in order to be withdrawn from the tapes. The trapezoidal shape of end punch 60 overcomes this problem since the oblique side walls act not only to urge the fastener elements to the left, i.e., toward the center of the gap, but in addition, provide sufiicient clearance in the slot to seize and withdraw the severed coupling elements in a manner similar to that provided by main punch 62 as shown in FIGS. 5 and 6.

Thus, while end punch 58 completely removes the fastener elements at the left end of the gap, end punch 60 serves to make a clean transverse cut through the filamentary stringers at the right edge of the gap and acts in concert with main punch 62 to force the lower legs of the coupling elements against the sharp cutting edges of slot 38 and subsequently seize and withdraw the same into the slot. In this manner, both the right and left ends of the gap are efficiently cleaned for providing a fragment free gap of any desired length. Thus, by shaping the right end punch 60 to provide a generally trapezoidal cross-section, the unsymmetrical nature of the coiled filamentary slide fastener chain is effectively accommodated thereby obviating slider fouling in completed slide fasteners and enabling the production of a finished product of superior quality.

Many of the advantages of the present invention can be seen in the above described simple method by which slide fastener chin of the coiled filamentary type is gapped and cleaned, which method may be summarized as including essentially the steps of positioning a group of interengaged fastener elements over a slot defined by a die member, positioning an end punch above the group of elements, the punch member. having a generally trapezoidal cross-section, moving the punch member into the slot such that its wider parallel wall cooperates with a transverse end wall of the slot to cut the filamentary stringers at a gap edge, engaging the cut stringers with the punch member to force a lower leg thereof against the edges of the slot to sever the fastener elements, and seizing the severed fastener elements by the oblique walls of the punch member and the side walls of the slot to urge the elements away from the gap edge while simultaneously withdrawing the same from the carrier tapes.

Thus, the present invention provides a simple apparatus and an effective method for removing the coupling elements of coiled type slide fastener chain from an area to be gapped without leaving loose coil chips or fragments at the gap ends.

Inasmuch as the present invention is subject to many variations, modifications and changes in detail, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:-

1. A method for cutting and cleaning a gap end in a slide fastener chain of the type having a plurality of interconnected fastener elements forming a pair of coiled filamentary stringers each attached along adjacent edges of a respective one of a pair of carrier tapes by threads extending around each coil of the filamentary stringers and with the fastener elements interengaged, the method comprising the steps of;

positioning a group of interengaged filamentary fastener elements over an elongated slot defined by a die member;

positioning an end punch member above said group of elements, said punch member being adapted to move into and out of said slot and having a a generally trapezoidal cross-section with the wider parallel wall dimensionally equal to the width of said slot;

moving said punch member into said slot such that said wider parallel wall cooperates with a transverse end wall of said slot to cut the filamentary stringers so as to define a gap edge;

engaging said out stringers with said punch member such that continued movement of said punch member forces a lower leg of the fastener elements against the edges of said slot to sever said fastener elements; and

grasping said severed fastener elements between the oblique side walls of said end punch member and the longitudinal side walls of said slot to urge said severed fastener elements away from said gap edge while simultaneously withdrawing the same from the carrier tapes.

2. The method of claim 1 wherein said die member defines a longitudinal channel in an upper surface thereof with said slot opening centrally onto the floor of said channel, and wherein said first positioning step includes placing said group of interengaged filamentary fastener elements in said channel.

3. A method for gapping and cleaning slide fastener chain of the type having a pair of interengaged coiled filamentary stringers, each having a plurality of interconnected coupling elements attached to a longitudinal edge of a carrier tape, the method comprising the steps of;

supporting the interengaged coiled filamentary stringers over a die member defining a slot;

cutting at least one coupling element of each of the interengaged coiled filamentary stringers at first and second spaced points along the chain to define the ends of a gap, said first point delineating the bottom end of an individual slide fastener and said second point delineating the top end of an adjacent individual slide fastener;

said cutting step including completely severing a first plurality of coupling elements in said gap at said first point with a first punch member cooperating with said die and having a generally rectangular cross-section, and severing a second plurality of coupling elements in said gap at said second point with a second punch member cooperating with said die and having a generally trapezoidal crosssection;

severing one leg of the coupling elements in said gap between said first and second points with a third punch member cooperating with said die;

engaging all of the severed coupling elements in said gap with said second and third punch members; and

moving said second and third punch members further into said slot to withdraw all of said severed coupling elements from the carrier tapes for providing an element-free gap having fragmentfree ends.

4. The method of claim 3 wherein said step of severing a second plurality of coupling elements includes moving said second punch member into said slot such that the wider parallel wall of said second punch member slidably engages a transverse end wall of said slot to cut the filamentary stringers so as to define a gap edge.

5. The method of claim 3 wherein said die member defines a longitudinal channel in an upper surface thereof with said slot opening onto the floor of said channel, and wherein said supporting step includes positioning the interengaged coiled filamentary stringers in said channel with the coupling elements partially overlying said slot.

6. Apparatus for cutting and cleaning a gap end in slide fastener chain of the type having a pair of interengaged helically coiled filamentary stringers, each attached to a respective one of a pair of carrier tapes, comprising die means defining a slot and adapted to support the slide fastener chain with the interengaged filamentary stringers overlying said slot, and

punch means reciprocally movable into and out of said slot and having a generally trapezoidal crosssection, said punch means having first and second parallel walls, said first parallel wall being disposed for sliding engagement with a transverse end wall of said slot and having a lateral dimension equal therewith, and said second parallel wall having a lateral dimension less than the transverse dimension of said slot.

7. The invention as recited in claim 6 wherein said die means defines a longitudinal channel with said slot opening onto the floor thereof, the floor of said channel including first and second oblique surfaces, each joining a respective longitudinal side wall of said slot to from a pair of cutting edges for said coupling elements.

8. The invention as recited in claim 7 wherein said die means includes a removable die key defining said transverse end wall of said slot and having an upper surface contiguously formed with the floor of said channel.

9. The invention as recited in claim 6 wherein the lateral dimension of said second parallel wall is larger than the transverse dimension of said slot less twice the cross-sectional dimension of the filamentary stringers.

10. Apparatus for gapping and cleaning slide fastener chain of the type having a pair of interengaged coiled filamentary stringers, each having a plurality of interedge of a carrier tape, comprising die means defining an elongated slot therein for supporting the slide fastener chain with the interengaged filamentary stringers overlying said slot,

main punch means movable into and out of said slot for forcing the lower leg of a plurality of coupling elements against the edges of said slot to sever said lower legs, said main punch means having a lateral dimension less than the width of said slot and engaging said severed coupling elements upon further movement into said slot to urge the same into said slot so as to withdraw said severed coupling elements from the carrier tapes,

first end punch means disposed adjacent a first end of said main punch means and movable into and out of said slot, said first end punch means having a generally rectangular cross-section and cooperating with a first end of said slot to cut at least one coupling element of each filamentary stringer so as to define a first gap end, and

second end punch means disposed adjacent a second end of said main punch means and movable into and out of said slot, said second end punch means having a generally trapezoidal cross section with the narrower parallel wall abutting said second end 25 of said main punch means, said second end punch means cooperating with a second end of said slot to transversely cut the filamentary stringers so as to define a second gap and and engaging those coupling elements of each filamentary stringer located between said second gap end and said main punch means upon further movement into said slot to force the same from the carrier tapes and into said slot whereby the severed coupling elements are removed from the tapes to provide an element-free gap.

11. The invention as recited in claim 10 wherein said die means includes a a removable die key defining said second end of said slot, said die key having a centrally crested upper surface intersecting the longitudinal side walls of said slot to form a pair of cutting edges.

12. The invention as recited in claim 10 wherein the upper edge of said slot is defined by a floor of or a longitudinal channel formed in said die means.

13. The invention as recited in claim 10 wherein the wider parallel wall of said second end punch means is dimensionally equal to the width of said slot. I

14. The invention as recited in claim 13 wherein the narrower parallel wall of said second end punch means is dimensionally equal to the width of the said main punch means. 

1. A method for cutting and cleaning a gap end in a slide fastener chain of the type having a plurality of interconnected fastener elements forming a pair of coiled filamentary stringers each attached along adjacent edges of a respective one of a pair of carrier tapes by threads extending around each coil of the filamentary stringers and with the fastener elements interengaged, the method comprising the steps of; positioning a group of interengaged filamentary fastener elements over an elongated slot defined by a die member; positioning an end punch member above said group of elements, said punch member being adapted to move into and out of said slot and having a generally trapezoidal cross-section with the wider parallel wall dimensionally equal to the width of said slot; moving said punch member into said slot such that said wider parallel wall cooperates with a transverse end wall of said slot to cut the filamentary stringers so as to define a gap edge; engaging said cut stringers with said punch member such that continued movement of said punch member forces a lower leg of the fastener elements against the edges of said slot to sever said fastener elements; and grasping said severed fastener elements between the oblique side walls of said end punch member and the longitudinal side walls of said slot to urge said severed fastener elements away from said gap edge while simultaneously withdrawing the same from the carrier tapes.
 2. The method of claim 1 wherein said die member defines a longitudinal channel in an upper surface thereof with said slot opening centrally onto the floor of said channel, and wherein said first positioning step includes placing said group of interengaged filamentary fastener elements in said channel.
 3. A method for gapping and cleaning slide fastener chain of the type having a pair of interengaged coiled filamentary stringers, each having a plurality of interconnected coupling elements attached to a longitudinal edge of a carrier tape, the method comprising the steps of; supporting the interengaged coiled filamentary stringers over a die member defining a slot; cutting at least one coupling element of each of the interengaged coiled filamentary stringers at first and second spaced points along the chain to define the ends of a gap, said first point delineating the bottom end of an individual slide fastener and said second point delineating the top end of an adjacent individual slide fastener; said cutting step including completely severing a first plurality of coupling elements in said gap at said first point with a first punch member cooperating with said die and having a generally rectangular cross-section, and severing a second plurality of coupling elements in said gap at said second point with a second punch member cooperating with said die and having a generally trapezoidal cross-section; severing one leg of the coUpling elements in said gap between said first and second points with a third punch member cooperating with said die; engaging all of the severed coupling elements in said gap with said second and third punch members; and moving said second and third punch members further into said slot to withdraw all of said severed coupling elements from the carrier tapes for providing an element-free gap having fragment-free ends.
 4. The method of claim 3 wherein said step of severing a second plurality of coupling elements includes moving said second punch member into said slot such that the wider parallel wall of said second punch member slidably engages a transverse end wall of said slot to cut the filamentary stringers so as to define a gap edge.
 5. The method of claim 3 wherein said die member defines a longitudinal channel in an upper surface thereof with said slot opening onto the floor of said channel, and wherein said supporting step includes positioning the interengaged coiled filamentary stringers in said channel with the coupling elements partially overlying said slot.
 6. Apparatus for cutting and cleaning a gap end in slide fastener chain of the type having a pair of interengaged helically coiled filamentary stringers, each attached to a respective one of a pair of carrier tapes, comprising die means defining a slot and adapted to support the slide fastener chain with the interengaged filamentary stringers overlying said slot, and punch means reciprocally movable into and out of said slot and having a generally trapezoidal cross-section, said punch means having first and second parallel walls, said first parallel wall being disposed for sliding engagement with a transverse end wall of said slot and having a lateral dimension equal therewith, and said second parallel wall having a lateral dimension less than the transverse dimension of said slot.
 7. The invention as recited in claim 6 wherein said die means defines a longitudinal channel with said slot opening onto the floor thereof, the floor of said channel including first and second oblique surfaces, each joining a respective longitudinal side wall of said slot to from a pair of cutting edges for said coupling elements.
 8. The invention as recited in claim 7 wherein said die means includes a removable die key defining said transverse end wall of said slot and having an upper surface contiguously formed with the floor of said channel.
 9. The invention as recited in claim 6 wherein the lateral dimension of said second parallel wall is larger than the transverse dimension of said slot less twice the cross-sectional dimension of the filamentary stringers.
 10. Apparatus for gapping and cleaning slide fastener chain of the type having a pair of interengaged coiled filamentary stringers, each having a plurality of interconnected coupling elements attached to a longitudinal edge of a carrier tape, comprising die means defining an elongated slot therein for supporting the slide fastener chain with the interengaged filamentary stringers overlying said slot, main punch means movable into and out of said slot for forcing the lower leg of a plurality of coupling elements against the edges of said slot to sever said lower legs, said main punch means having a lateral dimension less than the width of said slot and engaging said severed coupling elements upon further movement into said slot to urge the same into said slot so as to withdraw said severed coupling elements from the carrier tapes, first end punch means disposed adjacent a first end of said main punch means and movable into and out of said slot, said first end punch means having a generally rectangular cross-section and cooperating with a first end of said slot to cut at least one coupling element of each filamentary stringer so as to define a first gap end, and second end punch means disposed adjacent a second end of said main punch means and movable into and out of said slot, said second end punch means having a genErally trapezoidal cross-section with the narrower parallel wall abutting said second end of said main punch means, said second end punch means cooperating with a second end of said slot to transversely cut the filamentary stringers so as to define a second gap end and engaging those coupling elements of each filamentary stringer located between said second gap end and said main punch means upon further movement into said slot to force the same from the carrier tapes and into said slot whereby the severed coupling elements are removed from the tapes to provide an element-free gap.
 11. The invention as recited in claim 10 wherein said die means includes a removable die key defining said second end of said slot, said die key having a centrally crested upper surface intersecting the longitudinal side walls of said slot to form a pair of cutting edges.
 12. The invention as recited in claim 10 wherein the upper edge of said slot is defined by a floor of a longitudinal channel formed in said die means.
 13. The invention as recited in claim 10 wherein the wider parallel wall of said second end punch means is dimensionally equal to the width of said slot.
 14. The invention as recited in claim 13 wherein the narrower parallel wall of said second end punch means is dimensionally equal to the width of the said main punch means. 